DE10232982B4 - Method and arrangement for receiving-side detection of the associated data channels of time-multiplexed transmitted data signals - Google Patents

Abstract

method to monitor of time-division multiplexed Data signals, the transmitter side according to the HDLC protocol in data blocks with each a flag byte (F) are divided at the beginning and end, where these data blocks in the distribution to be determined on the channels of a PCM frame structure be characterized in that at several successive PCM frame in each case determines a flag byte (F) containing channels and from the contents of the following channels or the ones in front channels in the subsequent PCM frame of these flag channels those related channels be determined, which together each have a data block after the Transfer HDLC protocol.

Description

The The invention relates to a method according to the preamble of the claim 1 and an arrangement for execution This method according to claim 7.

It is known to use for rapid transmission of large amounts of data from a transmitter to a receiver, a so-called pulse-code modulation (PCM) frame structure in which the data are each time-slots in a plurality of time-slots transmitted in time-division multiplex. A commonly used PCM frame structure is, for example, PCM 30 or PCM 31, with which a data stream of 2 Mbit / s can be transmitted. 1 schematically shows this PCM frame structure. Here are 32 time channels TS combined to form a frame, the channels TS are numbered from 0 to 31. Each channel contains 1 byte or 8 bits. The step speed of the data of a channel is 64 kbit / s. The multiplexing of all 32 channels creates a data stream of 32 × 64 kBit / s = 2048 kBit / s. For example, in the PCM 31 structure, channel 0 contains frame synchronization, but no traffic data. The channels 1 to 31 contain the traffic or user data. In the PCM 30 structure, the channel 0 is designed as in PCM 31, the channel 16 contains, among other things, the signaling data and the so-called multiframe alignment signal, but again no traffic data. The remaining thirty channels contain the actual user or traffic data. (Digital transmission technology PCM basics and measuring methods, Expertverlag, Oskar Heilemann, page 26)

at This PCM frame structures is usually also of the possibility Made use of, data signals with higher data rate than 64 kbit / s on several channels distributed to transfer. A data stream of z. B. 256 kBit / s then requires four time channels TS. The Location of these channels assigned to a particular stream within The multiplex structure is arbitrary. The operators of the data connection are the chosen ones Associations known and chosen Nesting can simply be deinterleaved at the receiving end become. It becomes difficult when such a nested traffic tactically and strategically monitored and the supervisor it is not known in what way in the received PCM coded data stream of 2Mbit / s the information is distributed on the usable channels are.

2 shows an example of a possible distribution of different traffic data in a PCM 30 or PCM 31 frame. In this example, six different data signals with different data rates and different distribution are distributed in the frame. For a monitoring operator (supervisor) the combination possibilities for recognizing the associated data channels are so extremely high that manual attempts are futile in the case of ignorance of this channel selection selected for the channel. Although the supervisor can detect a data stream of 2 Mbps, it is not aware of how many independent sets of data streams are included at what data rate and how each data stream is located in the 64 Kbps grid of the PCM frame.

From the US 5,144,623 a method is known for receiving-side detection of time-multiplexed data signals. In this case, the data signal according to the HDLC protocol is divided into data blocks on the transmitter side, wherein the individual HDLC frames are separated by flag bytes. At the receiving end, a decoding of the HDLC frames is performed.

From the DE 29 48 435 C2 A method is known for transmitting four audio program signals in the pulse frame of the PCM 30, in which a plurality of successive channels are assigned to the data signal to be transmitted.

It is therefore an object of the invention, a method and an arrangement show, with the or the receiving side automatically one for the supervisor unknown channel distribution of the PCM frame structure can be determined can, so that monitoring Also, such PCM-coded data signals is possible.

These The object is with regard to the method starting from a method according to the preamble of claim 1 by its characterizing features and with regard to the arrangement by the features of the claim 7 solved.

advantageous Further developments emerge from the subclaims.

The Invention is based on the recognition that in such PCM-coded Data signals the data streams usually according to the so-called High Level Data Link Control (HDLC) protocol in data blocks being a characteristic of this HDLC protocol is that am The beginning and end of each data block is provided in each case a so-called flag byte. (Lexikon der Datenkommmunikation, Klaus Lipinski, International Thompson Publishing, page 246)

3 shows the standardized structure of this HDLC protocol. The flags F signalize the Beginning and end of the protocol, they are also used for block synchronization and they consist of the characteristic bit sequence 0-1-1-1-1-1-1-0. Subsequent to a flag byte F is followed by an address byte A, which contains the address of the remote station. In a subsequent control byte S, the commands and responses are included, with multiple data blocks, the sequence number is incremented. In the actual data block D, the user or traffic data are transmitted, wherein 2 bytes P are each still provided for the identifier of the inner protocol of the user data D. At the end of the payload data block D, there follows a check byte C, which contains the so-called cyclic redundancy check CRC as 16-bit check information and comprises the entire HDLC block with the exception of the flag bytes. Due to this HDLC characteristic byte sequence F, A, S, P and C, it is possible to detect the occupancy of a PCM frame with different traffic data despite the extremely fast data transmission. The data of the data channels thus recognized as belonging together can then be decoded and evaluated.

The Invention will be described below with reference to a schematic drawing on an embodiment explained in more detail. In show the drawing:

1 a PCM frame structure with 2048 kbps;

2 the assignment of a PCM frame with several different traffic data;

3 the HDLC protocol construction;

4 the matrix structure of the content in the PCM Diagram field "TS Frame";

5 characteristic points in the PCM diagram field "TS frame" for finding grouped signals (analysis matrix)

6 a flowchart for determining the edge zones of a grouped signal and

7 the basic structure of an inventive arrangement for automatically carrying out the method according to the invention.

• 1. Auslesen einer hinreichend großen Anzahl von PCM-Rahmen und der darin enthaltenen Kanäle TS gemäß der Matrixstruktur nach 4.
• 2. Suchen nach Flags (Flag-Bytes) F mit dem Muster "0 1 1 1 1 1 1 0" innerhalb der erfaßten Matrixstruktur.
• 3. Registrieren der TS, die solche Flags enthalten; z. B. TS 7 im Rahmen 0(RO) von 4.
• 4. Automatisches Eintragen der Flags F in eine Analyse-Matrix nach 5. Diese dient dazu, eine Übersicht zu schaffen, um die Strukturen der gruppierten Signale ausfindig zu machen. Es sollen in diesem Feld die Flags und die unmittelbar folgenden, markanten TS für alle gruppierten Signale eingetragen und bewertet werden, also A, S, P und C.
• 5. Aufsuchen derjenigen und als markant oder für die Analyse als relevant zu bezeichnenden TS, die den Flags zeitlich folgend zuzuordnen sind. Diese TS, die dem Flag folgen, müssen in der Analyse-Matrix nicht notwendigerweise zusammenhängend auftreten. Sie können in folgender Konfiguration erscheinen: • Unmittelbar zusammenhängend in einem Rahmen • Mit Unterbrechung aber innerhalb eines Rahmens (verschachtelt, gruppiertes Signal) • Mit Unterbrechung im nachfolgenden Rahmen
• 6. Bewerten der Eintragungen in der Anlayse-Matrix zum Erkennen der gruppierten Signalstrukturen (5). Es sollen, soweit wie möglich, Anfang und Ende der gruppierten Signale im PCM-Rahmen erkennbar werden. Die Auswertung erfolgt anhand der Eintragungen im Feld "TS-Rahmen" über die Zeit, also anhand der zur Verfügung stehenden Rahmen. Die Flags F bilden die Stützstellen für die Bewertung der nachfolgenden, markanten Bytes A, S, P und C. Die Flags sind im Normalfall gefolgt von 4 Bytes, die folgende Bedeutung haben: • Es wird 1 Byte A für die Adresse ADR der Zielstation (z. B. Hex 00 bis FF) verwendet. • Es dient 1 Byte S für das Steuerfeld STEU; es kann zur Kennung bestimmter äußerer Protokolle (z. B. Hex 00 für CiscoSLE, Hex 03 für PPP) verwendet werden; sonst hat es eine andere Bedeutung. • Es werden 2 Bytes P für die Kennung des inneren Protokolls, (z. B. Internet Protokoll IP), in dem sich die Nutzdaten befinden, verwendet. Um diese Protokolle ausreichend interpretieren zu können, wird im Hintergrund eine Tabelle geführt, mit der die Inhalte der TS 3 und 4 nach dem Flag verglichen werden.
• 7. Bestimmung der Struktur zu den gruppierten Signalen im PCM-Rahmen. Dazu werden die markanten TS, die den Flags unmittelbar folgen, im weiteren näher untersucht. Dabei kommt es insbesondere auf die Lage der ursprünglich zusammenhängend gesendeten Pakete (Flag, ADR, STEU, Protokoll) in den PCM-Rahmen an; beim Einspeisen in den PCM-Rahmen ergibt sich aufgrund der Gruppierung eine gewisse "Neuordnung", wenn man die Kontinuität des PCM-Rahmens betrachtet. • Einem Flag muß zwingend eine Adresse ADR folgen; ist dies in der Matrix-Struktur im Feld "TS-Rahmen" nicht unmittelbar der Fall, so ist daraus zu schließen, daß sich das Flag am Rande eines gruppierten Signals befindet, und zwar im letzten TS des gesuchten Gruppensignals. Damit ist eine Randzone eines gruppierten Signals bestimmt worden. Das Auffinden der zu diesem Flag zugehörigen Bytes (ADR, STEU, Protokoll) dient dazu, auch die zweite Randzone für dieses gruppierte Signal zu ermitteln. Die zugehörigen Bytes müssen entweder im gleichen Rahmen an anderen TS nach dem Flag (verschachtelt, gruppiertes Signal) oder im Folgerahmen an TS vor dem Flag erfolgen. Eine gewisse Eingrenzung, wo die zugehörigen Bytes zu finden sein werden, ist damit erfolgt.

In the example chosen, it is assumed that the received 2 Mbit / s data stream is transmitted to a total of 31 channels TS according to a PCM 30 or PCM 31 frame structure, namely according to the HDLC protocol according to FIG 3 divided into arbitrarily long data blocks with arbitrarily long user data streams D. The bits received consecutively in rapid succession in the individual channels TS are initially set according to FIG 4 as successive PCM frames are read into a matrix structure. The procedure is as follows:

• 1. Reading a sufficiently large number of PCM frames and the channels TS contained therein according to the matrix structure according to 4 ,
• 2. Search for flags (flag bytes) F with the pattern "0 1 1 1 1 1 1 0" within the detected matrix structure.
• 3. Register the TS containing such flags; z. TS 7 in frame 0 (RO) of 4 ,
• 4. Automatic entry of flags F into an analysis matrix 5 , This serves to provide an overview in order to locate the structures of the grouped signals. In this field, the flags and the immediately following, striking TS for all grouped signals should be entered and evaluated, ie A, S, P and C.
• 5. Searching for those TSs that are to be designated as relevant or relevant for the analysis, which are to be assigned to the flags in chronological order. These TSs that follow the flag need not necessarily be contiguous in the analysis matrix. They can appear in the following configuration: • Immediately connected in a frame • Intermittently but within a frame (interlaced, grouped signal) • Interrupted in the following frame
• 6. Evaluate the entries in the analysis matrix to recognize the grouped signal structures ( 5 ). As far as possible, the beginning and end of the grouped signals in the PCM frame should become recognizable. The evaluation takes place on the basis of the entries in the field "TS frame" over the time, thus on the basis of the available frames. The flags F form the support points for the evaluation of the subsequent significant bytes A, S, P and C. The flags are normally followed by 4 bytes, which have the following meaning: 1 byte A for the address ADR of the destination station ( eg Hex 00 to FF). • 1 byte S is used for the STEU control field; it can be used to identify certain external protocols (eg Hex 00 for CiscoSLE, Hex 03 for PPP); otherwise it has a different meaning. 2 bytes P are used for the ID of the inner protocol (eg Internet Protocol IP) in which the payload is located. In order to be able to interpret these protocols sufficiently, a table is run in the background with which the contents of TS 3 and 4 are compared according to the flag.
• 7. Determination of the structure of the grouped signals in the PCM frame. These are the mar edges TS, which immediately follow the flags, are examined in more detail below. In this case, the position of the originally coherently sent packets (flag, ADR, STEU, protocol) in the PCM frame is particularly important; when fed into the PCM framework, there is some "rearrangement" due to the grouping, considering the continuity of the PCM framework. • A flag must necessarily follow an address ADR; if this is not directly the case in the matrix structure in the "TS frame" field, it can be concluded that the flag is located at the edge of a grouped signal, namely in the last TS of the sought group signal. Thus, an edge zone of a grouped signal has been determined. Finding the bytes associated with this flag (ADR, STEU, Protocol) also serves to determine the second edge zone for this grouped signal. The associated bytes must either be in the same frame on the other TS after the flag (interleaved, grouped signal) or in the subsequent frame on TS in front of the flag. A certain limitation, where the associated bytes will be found, is done with it.

• • Wenn ein Flag F mit den zugehörigen vier markanten Kanälen A, S und P als zusammenhängend entdeckt wird, liegt es irgendwie innerhalb eines gesuchten, gruppierten Signals; man kann daraus zunächst nur schließen, daß das gruppierte Signal mindestens 5 TS breit ist. Es kann aber auch breiter sein und das detektierte Signal kann sich in der Mitte oder an den Rändern eines gruppierten Signals befinden. (EinzelheitII). Mit dem "mittig gelegenen" Block dieser Sendung bestehend aus Flag, ADR, STEU, Protokoll kann keine Randzone ermittelt werden. Zur Bestimmung der Randzonen muß in den nachfolgenden Rahmen in der Nähe der TS-Position des "mittig" gelegenen Flags nach dem nächsten Flag dieser Sendung gesucht werden. Abhängig von der Lage des nächsten, in dieser Region entdeckten Flags mit den markanten, zugehörigen (4) TS in anderen Rahmen, kann dann erkannt werden, ob sich die neue Konstellation zur Bestimmung von Randzonen eignet oder nicht. Wenn die zusammengehörigen TS Flag, ADR, STEU, Protokoll in der Analyse-Matrix nicht zusammenhängend erscheinen, können die Randzonen wie oben beschrieben ermittelt werden. Falls die neue Konstellation Flag, ADR, STEU, Protokoll wieder zusammenhängend auftritt, können nur deren Anfangs- und Ende-TS registriert werden. Im Vergleich zur ersten zusammengehörigen TS-Gruppe kann man nur anhand einer eventuellen Verschiebung zwischen diesen beiden über die Breite des gruppierten Signals etwas mehr aussagen. Die Randzonen des gruppierten Signals sind aber noch nicht hinreichend bestimmt.
• • Sollten mehrere Gruppen von zusammengehörigen, markanten TS zusammenhängend zeitlich nacheinander in den Rahmen erscheinen, ohne eine "aufgetrennte Gruppe" für diese Sendung vorzufinden, so wird am Ende der Auswertung die Lage dieser Sendung anhand der gesamten Gruppierung in dem PCM-System mitbestimmt. Eine eventuelle Unsicherheit für ein gruppiertes Signal wird anhand der Zuverlässigkeitsfaktoren, die die Nachbarsignale aufweisen, korrigiert.
• • Schwieriger wird es, wenn der Header-Block (Flag, ADR, STEU, Protokoll) geteilt an zwei verschiedenen TS-Bereichen im gleichen Rahmen auftritt, also verschachtelt zwischen anderen gruppierten Signalen, angeordnet wurde. In diesem Fall muß zwischen anderen, markanten Bytes unterschieden werden, die zu anderen gruppierten Signalen gehören und möglicherweise sich auch noch nebeneinander in dem PCM-Rahmen befinden. In solchen Fällen müssen dann Fallentscheidungen nach Plausibilitätskriterien getroffen werden, die übergreifend zwischen benachbarten Gruppen eingesetzt werden. Anhand der vorliegenden Konstellation wird entschieden, welche TS zu welchem Flag/gruppierten Signal noch zu rechnen sind. Dies ist erst dann möglich, wenn 2 aufeinanderfolgende Rahmen bewertet wurden. Die TS-Grenzen/Lagen eines verschachtelt, gruppierten Signals werden vor allem dann immer eindeutiger, je mehr Rahmen zur Auswertung herangezogen werden können. Wenn Sendungen mit sehr langem Dateninhalt auftreten, gibt es wenige Flags einschließlich der zugehörigen, markanten Bytes; in solchen Fällen muß die Anzahl der zu bewertenden Rahmen entsprechend groß sein. (Bei 2048 kBit/s fallen 8000 Rahmen pro Sekunde an; eine Beobachtungszeit von einigen Sekunden dürfte auch in solchen Fällen ausreichen.)
• • Wenn das Feld "TS-Rahmen" auf diese Weise ausgewertet wird, entstehen die Strukturen zum Erkennen der gruppierten Signale in einem PCM-Rahmen. Bei kurzen Auswertezeiten der Analyse-Matrix und bei teilweise lang andauernden Einzelsendungen entstehen Strukturen, die noch nicht zugewiesene TS/Kanäle enthalten. Diese sind aber dann erkennbar und können bei einer graphischen Darstellung entsprechend gedeutet werden. Gleiches gilt für nicht belegte TS/Kanäle. (TS Nummer 1 bis 4 und 20 bis 31, in 4 mit I bezeichnet)
• • In Einzelfällen können Mehrdeutigkeiten derart auftreten, daß nebeneinanderliegende Nutzdaten und Headerdaten innerhalb eines Rahmens nicht mehr trennbar sind. Bei den verschachtelt, gruppierten Signalen können solche Fälle auftreten. Diese Unsicherheiten führen zwar kurzzeitig zu ungenauen Strukturen, sind aber von geringerer Bedeutung, da die endgültige Bewertung über die Struktur der gruppiert auftretenden Signale in einem PCM-Rahmen erst nach einer geeignet wählbaren Auswertezeit ausgegeben wird, die dann entsprechend viele Rahmen bei der Endauswertung berücksichtigt und einzelne, in der Minderheit befindliche Abweichungen, werden dann eliminiert.
• • Jedes ermittelte und registrierte Ergebnis über eine Lage eines gruppierten Signals erhält einen Zuverlässigkeitsfaktor, der ausdrückt, ob das Ergebnis anhand von getrennten oder zusammenhängenden markanten TS gebildet wurde. Zusätzlich wird die Anzahl der Stützstellen (Flags), auf die sich das Ergebnis stützt, einbezogen. Bei den "getrennt" auftretenden markanten TS ist die Bestimmung der Lagen eindeutig und unabhängig von benachbarten Signalen. Sie erhalten deshalb einen hohen Zuverlässigkeitsfaktor. Bei zusammenhängend auftretenden, markanten TS ist die Bestimmung der Lage eines gruppierten Signals auch abhängig von den Nachbarsignalen; sie erhalten einen niedrigeren Zuverlässigkeitsfaktor.

If the associated bytes are in the next frame, another constraint criterion must be set to eliminate ambiguity between the grouped signals; those TSs that are in the immediate vicinity of the considered flag, but in the next frame, are considered to belong to the considered flag. These TSs must be located forcibly on the "left edge" of the grouped signal (detail I) as they represent the continuation to the considered flag and therefore must begin at the beginning of the "left edge zone". This completely captures the TS assignment of a grouped signal based on 2 frames. The two fringes, that is the location of the grouped signal, are included in the analysis matrix as a result. To achieve more security over the TS assignment of a grouped signal, additional frames are evaluated and registered in the same way.

• • If a flag F with the associated four distinct channels A, S and P is found to be contiguous, it is somehow within a searched, grouped signal; one can only conclude that the grouped signal is at least 5 TS wide. It may also be wider and the detected signal may be in the middle or at the edges of a grouped signal. (EinzelheitII). With the "center" block of this program consisting of flag, ADR, STEU, protocol no border zone can be determined. To determine the edge zones, the next frame in the vicinity of the TS position of the "center" flag must search for the next flag of this transmission. Depending on the location of the next flag detected in this region with the distinctive, associated (4) TS in other frames, it can then be recognized whether the new constellation is suitable for determining edge zones or not. If the associated TS Flag, ADR, STEU, Protocol do not appear contiguous in the analysis matrix, the fringes can be determined as described above. If the new constellation Flag, ADR, STEU, Protocol again cohesively occurs, only their start and end TS can be registered. Compared to the first associated TS group, it is only possible to say something more about the width of the grouped signal due to a possible shift between the two. The fringes of the grouped signal are not yet sufficiently determined.
• • If several groups of related, distinctive TS appear consecutively in the frame consecutively, without finding a "split group" for this broadcast, then at the end of the evaluation, the situation of this broadcast is determined by the total grouping in the PCM system. Any uncertainty for a grouped signal is corrected based on the reliability factors exhibited by the neighboring signals.
• • It becomes more difficult if the header block (flag, ADR, STEU, protocol) is divided into two different TS areas in the same frame, ie nested between other grouped signals. In this case, a distinction must be made between other distinctive bytes belonging to other grouped signals and possibly also located side by side in the PCM frame. In such cases case decisions must then be made according to plausibility criteria, which are used across all neighboring groups. On the basis of the present constellation it is decided which TS to which flag / grouped signal are still to be expected. This is only possible if 2 consecutive frames have been evaluated. The TS boundaries / positions of a nested, grouped signal become more and more clear, in particular, the more frames that can be used for the evaluation. When broadcasts with very long data content occur, there are few flags including the associated distinctive bytes; in such cases, the number of frames to be evaluated must be correspondingly large. (At 2048 kbps, 8000 frames per second occur, and a few seconds observation time may be sufficient in such cases.)
• • If the box "TS Frame" in this way is evaluated, the structures are created to recognize the grouped signals in a PCM frame. With short evaluation times of the analysis matrix and with partially long-lasting individual transmissions, structures arise that contain unassigned TS / channels. These are then recognizable and can be interpreted accordingly in a graphical representation. The same applies to unoccupied TS / channels. (TS number 1 to 4 and 20 to 31, in 4 denoted by I)
• • In individual cases, ambiguities may occur in such a way that adjacent user data and header data within a frame are no longer separable. Such cases may occur with nested, grouped signals. Although these uncertainties lead to inaccurate structures for a short time, they are of lesser importance since the final evaluation of the structure of the grouped signals in a PCM frame is output only after a suitably selectable evaluation time, which then takes into account a corresponding number of frames in the final evaluation and individual, minority deviations are then eliminated.
• • Each detected and registered result over a location of a grouped signal receives a reliability factor that expresses whether the result was based on separate or contiguous distinctive TSs. In addition, the number of nodes (flags) on which the result is based is included. For the distinctive TS occurring "separated", the determination of the positions is unambiguous and independent of adjacent signals. They therefore receive a high reliability factor. In the case of coherently occurring marked TS, the determination of the position of a grouped signal is also dependent on the neighboring signals; they get a lower reliability factor.

• • Ein PCM Datenstrom von 2 MBit/s kann derart entflechtet werden, daß gruppierte Signale in ihrer Lage erkannt werden und die Anzahl der jeweils benützten Datenkanäle offengelegt wird.
• • Die Datenrate für jedes gruppierte Signal wird ermittelt.
• • Gruppierte Signale, die verschachtelt/getrennt innerhalb des PCM-Rahmens auftreten, jedoch den Inhalt einer Sendung führen, werden erkannt und ihre Belegung der TS/Kanäle wird ausgegeben.
• • Falls die Gruppierung in dem PCM-Rahmen "dynamisch" erfolgen sollte, werden die gleichen Ergebnisse erzielt wie im statischen Zustand.
• • Die Umstellung der Gruppierung in dem PCM-Rahmen wird sofort erkannt und kann als Warnung abgegeben werden.
• • Jede Änderung in der Gruppierung wird sofort erfaßt und im Bedarfsfall gemeldet.
• • Die Zuordnungen für die gruppierten Signale erhalten Zuverlässigkeitsfaktoren, um auf eventuelle Sonderfälle aufmerksam zu werden.
• • Das Verfahren ist für PCM 30/31 einsetzbar.
• • Die Auslastung der Verkehrsverbindung ist erkennbar und kann registriert werden. (Anzahl der Einzelsendungen pro Verkehrsverbindung und Zeiteinheit einschließlich Testsequenzen).
• • Der Dateninhalt pro Verkehrverbindung kann aufgezeichnet und dekodiert werden.
• • Die Länge der Einzelsendungen pro Verkehrsverbindung wird erkannt; einschließlich eventueller Adressenänderungen.
• • Die Suche nach bestimmten Adressen kann aufgenommen werden.
• • Nicht HDLC-orientierte Datenblöcke werden erkannt und gemeldet.

The analysis matrix provides the following advantageous results with an appropriate evaluation in the overview:

• • A PCM data stream of 2 Mbit / s can be unbundled in such a way that grouped signals are recognized in their position and the number of data channels used is disclosed.
• • The data rate for each grouped signal is determined.
• • Grouped signals that appear nested / separated within the PCM frame but carry the contents of a program are recognized and their TS / channel assignment is output.
• • If the grouping in the PCM frame should be "dynamic", the same results are achieved as in the static state.
• • The change of the grouping in the PCM frame is recognized immediately and can be given as a warning.
• • Any change in the grouping is recorded immediately and reported if necessary.
• • The assignments for the grouped signals receive reliability factors in order to be aware of any special cases.
• • The method can be used for PCM 30/31.
• • The utilization of the traffic connection is recognizable and can be registered. (Number of individual consignments per traffic connection and time unit including test sequences).
• • The data content per traffic connection can be recorded and decoded.
• • The length of the individual consignments per traffic connection is recognized; including any address changes.
• • The search for specific addresses can be recorded.
• • Non HDLC-oriented data blocks are detected and reported.

6 shows a flowchart the described procedure for determining the edge zones of a grouped signal.

7 shows the basic structure of an inventive arrangement for automatically carrying out this described detection method.

The arrangement comprises a buffer 1 , several comparators 2 to 5 , which simultaneously act as short-term memory and those setpoint memory 6 to 9 are assigned, in which the known characteristic bit patterns of the HDLC protocol are stored. In the flag store 6 the known bit sequence 0-1-1-1-1-1-1-0 is stored in the address memory 7 the address of the remote station is stored in the control memory 8th the known control bits S are stored in the log memory 9 the two bytes P are stored for the identifier of the internal protocol of the payload. Further, an analysis memory 10 , a programming unit 11 and a display device 12 intended. The individual assemblies are in the sense of 7 linked together.

In the cache 1 First, the individual channels TS of the Zeitmulitplex frame are read continuously. The flag comparator 2 compares the bit patterns of the incoming channels with the one in the flag memory 6 stored flag pattern, if coincidence is detected, the flag comparator divides the detected channel number and frame number for each detected flag the other comparators 3 . 4 and 5 With. The comparators 3 . 4 and 5 compare the bit patterns of those channels following the detected flag channel with the bit patterns of the associated setpoint memory 7 . 8th and 9 , The thus recognized distinctive and HDLC-cha The subsequent characteristic channels are then sent to the analysis memory together with the flag channels 10 fed and there in the sense of 5 saved. The analysis memory 10 thus obtains a structure that builds the fringes of the associated data channels in the background. With a suitable programmer software 11 becomes this structure of analysis memory 10 evaluated with respect to the determined edge zones and the reliability factors mentioned are determined. In the display device 12 Finally, the time-multiplexed frames are displayed so that the associated grouped data channels contained therein can be recognized. In addition, the associated data rate and the determined reliability factor can be displayed. Via a decoding device, not shown, then recognized as belonging together channels can be evaluated.

The Display result is preferably at adjustable time intervals updated, in case of deviations from the previous result the new configuration to the data channels continuously in a new one Display line shown. With a dynamic allocation of the data channels one gets so an overview of that current and over the past Data transference.

Claims (8)

Method for monitoring time-division-multiplexed data signals, which are divided on the transmitter side according to the HDLC protocol into data blocks each having a flag byte (F) at the beginning and end, these data blocks being transmitted in a distribution to be determined on the channels of a PCM frame structure , characterized in that at several consecutive PCM frames each containing a flag byte (F) channels are determined and those related channels are determined from the content of the subsequent channels or the preceding channels in the subsequent PCM frame of these flag channels , which together transmit a data block according to the HDLC protocol. Method according to claim 1, characterized in that that together at least with the channels each containing a flag byte (F) a part of those channels Determines whichever of the HDLC protocol to the flag bytes (F) subsequent HDLC characteristic data bytes (A, S, P) included. Method according to claim 1 or 2, characterized that the determined channels in the form of a channel frame matrix be evaluated. Method according to one of the preceding claims, characterized characterized in that Determination of the related channels is performed on consecutive PCM frames multiple times. Method according to one of the preceding claims, characterized characterized in that in the so determined coherent Transmitted channels data blocks (D) decoded and evaluated. Method according to one of the preceding claims, characterized characterized in that Result of the determination of the related channels is displayed graphically. Arrangement for carrying out the method according to one or more of the preceding claims, characterized by a buffer ( 1 ) in which the successive PCM frames are read in, a flag comparator ( 2 ) which compares the bit patterns of the successive channels (TS) with the known flag bit pattern, at least one further comparator ( 3 . 4 . 5 ) comparing the bit patterns of the channels following the detected flag channel with at least one of the subsequent HDLC characteristic bit patterns, an analysis memory ( 10 ) in which the flag channels thus recognized and subsequent HDLC characteristic channels are stored, a programmer ( 11 ) for evaluating the content of the analysis memory ( 10 ), as well as a thereby controlled display device ( 12 ). Arrangement according to Claim 7, characterized in that the individual comparators ( 2 to 5 ) each memory ( 6 to 9 ) in which the known HDLC characteristic bit patterns (F, A, S, PP) are stored.